Polonius: This is the very ecstasy of love, Whose violent property fordoes itself and I had not quoted him : I fear'd he did but trufle, how do these lines reveal a deeper misunderstanding of Hamlet's true nature / conflicts ?

Polonius is convinced that Hamlet's madness is a result of unrequited love for Ophelia. Polonius likes to believe that forbidding his daughter to see Hamlet is the root of Hamlet's mental instability. Polonius likes to believe he has more control over situations than he actually does. Hamlet is actually using Polonius's plan to his advantage. He is using Ophelia to display his "mental instability" in order to carry out his plan for revenge. Polonius likes to project his own scheming manipulations as exposing truth: this is perhaps Polonius's tragic flaw.